Personal cleansing compositions which provide cleansing and personal care benefits are known in the art, for example, liquid cleansing market. In order to achieve superior mild and moisturizing skin benefit, very high levels (generally higher than 30% by wt. of liquid compositions) of emollient oils are used in leading marketed moisturizing compositions (e.g., Dove® Cream Oil or Olay® Ribbon body wash compositions).
There has been a continuous effort to provide skin care benefits from personal skin/hair cleanser compositions, for example, by delivering ever increasing amounts of benefit agents such as silicone oil, petrolatum and triglyceride oils from such cleansers. Some products use emollient oils as high as 50% by wt. or more of the composition.
U.S. Pat. No. 5,612,307 to Chambers et al. discloses, for example, use of a single package containing separate stripe of cleansing agents and benefit agents where benefit agent is as high as 50% of the package in order to deliver sufficient benefit agent for efficient skin moisturizing and conditioning. Delivery of benefit requires special packaging, complicated processing and high levels of benefit agent.
U.S. Pat. No. 5,965,500 to Puvvada discloses liquid compositions where the level of emollient exceeds the level of surfactant.
Other references also require very high level of skin benefit agent to deliver skin care benefits (U.S. Publication No. 2005/0100570 A1; U.S. Publication No. 2005/0143268 A1; U.S. Publication No. 2006/0079420 A1, all to Procter & Gamble). The benefit of using very mild surfactant systems to minimize use of benefit agent is not recognized.
Accordingly, there is a need for personal cleanser compositions (e.g., liquid cleansers) which provide superior skin care benefit without requiring use of high levels of benefit agent.
Unpredictably, applicants have found that this aim can be achieved using exceptionally mild surfactant mixtures. It is extremely surprising that the overall level of surfactant can be increased (relative to different systems) while also increasing mildness. Using surfactant systems of the invention, it is possible to achieve significant mildness (as defined in standard Patch Test as disclosed, for example, in Protocol below) while using, for example, much lower levels (e.g., 30% or less) of the types of occlusive emollient oils (e.g., petrolatum, silicone) typically used for providing mildness benefits. Clinical benefits are equal to or better than products tested which comprise, for example, 40% or more petrolatum.
Various other mild cleanser compositions have been claimed. Various references to Johnson & Johnson claim compositions comprising modified acrylic copolymers and common anionic surfactants such as sodium trideceth sulfate (U.S. Pat. No. 7,119,059; U.S. Pat. No. 7,098,180; U.S. Pat. No. 7,084,104; U.S. Publication No. 2005/0075256). U.S. Publication No. 2005/0192188 to Wagner et al. discloses surfactants with a structured domain comprising at least 70% of a lamellar phase made using common surfactant mixtures such as sodium trideceth sulfate and sodium laurylamphoacetate.
Compositions of the subject invention provide unique surfactant systems (using, for example, alkanoyl glycinate and specified fatty acyl isethionate surfactant products), preferably for use in compositions having little to no (e.g., 3% by wt. or less, preferably 2% by wt. or less) alkyl sulfate surfactants (e.g., sodium alkyl sulfate, sodium alkyl ether sulfate), which are common to many cleanser compositions.